DSS Racing FX Series Forged +4cc Dome Top Piston Set

Chrysler / Dodge / Jeep / Ram 6.1L SRT8 Gen III Hemi

1-6847-4065 / 2-6847-4065 / 3-6847-4065 / K1-6847-4065 / K2-6847-4065 / K3-6847-4065

Overview:

The DSS Racing FX Series Forged +4cc Dome Top Piston Set is engineered specifically for the 6.1L Gen III Hemi engines found in most Chrysler, Dodge, Jeep, and Ram SRT8 models. Designed to enhance engine performance and durability, these pistons offer a precision fit and increased combustion chamber volume with a +4cc dome top design. Ideal for enthusiasts and professional builders seeking reliable, high-quality components for street or track applications, this piston set delivers improved compression ratios and robust construction to handle increased power demands.

Whether upgrading a stock engine or building a high-performance small block Mopar Hemi, these pistons provide the strength and precision necessary for consistent, efficient combustion and long-term reliability.

Key Features:

Built with advanced engineering and performance in mind, the DSS Racing FX Series pistons include the following key features:

• Forged construction for superior strength and durability under high stress
• +4cc dome top design to optimize combustion chamber volume and compression ratio
• Comp height of 1.21 inches for precise piston-to-head clearance
• Pin diameter of .927 inches compatible with full-floating or press-fit configurations
• Ring groove dimensions of 1.2mm/1.2mm/3mm to accommodate high-performance piston rings
• Designed for 3.578-inch stroke and 6.243-inch connecting rods, matching factory Gen III Hemi specs
• Available in multiple combustion chamber volumes (65cc, 74cc, 85cc) to tailor compression ratios from 9.49:1 to 11.94:1
• Precision CNC machining ensures tight tolerances and consistent performance
• Compatible with 371 Small Block Mopar Hemi Gen III engines

Construction & Design:

These pistons are forged from high-grade aluminum alloy, providing an optimal balance of lightweight design and exceptional strength. The dome top shape increases the combustion chamber volume by +4cc, allowing for higher compression ratios that improve power output and efficiency. The pistons feature a comp height of 1.21 inches, engineered to maintain proper deck clearance and prevent piston-to-valve contact in high-performance builds.

The pin bore is designed to accept either full-floating or press-fit wrist pins, offering flexibility depending on engine build preferences. Ring grooves are precisely cut to accommodate performance ring sets, ensuring effective sealing and reduced blow-by. The pistons are tailored to fit the 3.578-inch stroke and 6.243-inch rod length of the 6.1L Gen III Hemi, guaranteeing a perfect fit and smooth operation.

Installation & Fitment:

This piston set is a direct fit for most Chrysler, Dodge, Jeep, and Ram 6.1L SRT8 Gen III Hemi engines, making it an excellent choice for OEM replacements or performance upgrades. Installation requires standard engine assembly procedures, including proper ring installation, wrist pin fitting, and torque specifications. No major modifications are necessary when used within compatible engine builds, but professional installation is recommended to ensure optimal performance and longevity.

What's Included:

• Set of forged +4cc dome top pistons (quantity as per engine requirements)
• Compatible wrist pin options (full-floating or press-fit)
• Detailed specifications for ring groove dimensions and piston geometry

Ideal For:

This piston set is ideal for performance enthusiasts, engine builders, and racers who demand enhanced durability and power from their 6.1L Gen III Hemi engines. It suits applications ranging from street performance upgrades to track-focused builds, providing improved compression and reliable operation under increased boost or naturally aspirated conditions. If you are upgrading your Chrysler, Dodge, Jeep, or Ram SRT8 engine for better throttle response, power gains, and long-term reliability, these DSS Racing pistons are an excellent choice.

DSS Racing — Founded in 1983 originally as Danny’s Speed Shop, DSS Racing has grown from a small Midwest performance engine shop into a respected name in forged engine components for the high-performance and racing markets. Based in St. Charles, Illinois, DSS is best known for its forged pistons and machined engine parts made in the USA that have been used in championship engines and thousands of builds, blending old-school racing roots with precision manufacturing for enthusiasts and racers alike.